Real-world risk factors for herpes zoster in patients with rheumatoid arthritis undergoing tofacitinib treatment

Background:This study sought to assess the risk factors of herpes zoster (HZ) in rheumatoid arthritis (RA) patients treated with tofacitinib (TOFA).Methods:This retrospective study reviewed RA patients receiving TOFA. We compared clinical characteristics, laboratory profiles, concomitant medication use, and HZ incidence in patients with and without recent biologic synthetic disease-modifying antirheumatic drugs (bDMARDs) treatment, which is defined as their administration <= 180 days before the initiation of TOFA treatment. We used univariate Cox proportional hazards models and Kaplan-Meier analysis to assess risk factors.Results:Among 304 RA patients, 97 had recent bDMARDs use and 207 did not. Patients with recent bDMARDs use typically had lower weekly doses of methotrexate, less hydroxychloroquine use, and shorter follow-up. In the recent bDMARDs group, 64 (66.0%) used tumor necrosis factor inhibitors (TNFi), 19 (19.6%) used tocilizumab, and 14 (14.4%) used abatacept. The overall incidence rate (IR) of HZ was 5.62 per 100 person-years. Patients with recent bDMARDs use exhibited a higher HZ risk compared to those without recent bDMARDs use (IR ratio: 2.34, 95% CI, 1.04-5.19, p = 0.028). Recent bDMARDs use (hazard ratio: 2.4, 95% CI, 1.12-4.95, p = 0.024) was an independent risk factor for HZ among multivariable analysis. Kaplan-Meier analysis confirmed increased HZ risk in RA patients on TOFA with recent bDMARDs use (log-rank p = 0.015).Conclusion:HZ is common in RA patients treated with TOFA, and recent bDMARDs (TNFi, tocilizumab, and abatacept) use is a risk factor for HZ. HZ vaccination, therefore, should be recommended for this group.